Device for controlling operating means for at least one electric illuminating means and a method for controlling operating means for at least one electric illuminating means

ABSTRACT

The invention relates to a device (C, C′) for controlling operating means ( 3, 3′ ) for at least one electric illuminating means ( 4, 4′ ). The inventive device comprises an input ( 8   a,    8   b,    8   a′,    8   b′ ) for receiving control signals from an external control device ( 7 ) and an evaluating means ( 9, 9′ ) that is suitable to detect analogous and digital control signals on the input ( 8   a,    8   b,    8   a′,    8   b′ ) for control signals and to evaluate said signals for controlling operating means ( 3, 3′ ) for the illuminating means ( 4, 4′ ). The invention also relates to a method for controlling the operating means ( 3, 3′ ) for electric illuminating means ( 4, 4′ ) by means of analogous or digital control signals. In an advantageous embodiment, the inventive device (C, C′) is a component of an operating device (B, B′) for electric illuminating means ( 4, 4′ ).

I. TECHNICAL FIELD

[0001] The invention relates to a device for controlling operating meansfor at least one electric illuminating means, and to a method forcontrolling operating means for at least one electric illuminatingmeans. The term electric illuminating means denotes both electric lampssuch as, for example, incandescent lamps or discharge lamps, andlight-emitting diodes.

II. BACKGROUND ART

[0002] The Laid-Open Specification EP 0 639 938 A1 describes a controldevice for consumers combined in groups. These consumers are, inparticular, operating devices for electric lamps that have a device inaccordance with the preamble of patent claim 1, and operating means forat least one electric lamp. These operating devices have a controlsignal input via which control signals can be applied to them by meansof the control device in order to implement different illuminatingscenarios. Digital control signals are required to control the operatingdevices.

III. DISCLOSURE OF THE INVENTION

[0003] It is the object of the invention to provide a device forcontrolling operating means for at least one electric illuminating meansand which can optionally be driven via the same control signal inputwith the aid of digital or analog control signals, and to specify amethod for controlling the operating means for at least one electricilluminating means and which permits the operating means to becontrolled optionally at the same control signal input with the aid ofdigital or analog control signals.

[0004] This object is achieved for a generic device according to theinvention by means of the features of patent claim 1, and for the methodaccording to the invention by means of patent claim 7. Particularlyadvantageous features of the invention are described in the subclaims.

[0005] The device according to the invention has evaluating means thatare suitable for automatically detecting both analog and digital controlsignals at the control signal input of the device, and for evaluatingthem for the purpose of controlling the operating means for theilluminating means. The device according to the invention can thereforebe used both in lighting systems that are fitted with central controldevices for generating analog control signals, and in lighting systemsthat are provided with central control devices for generating digitalcontrol signals. Moreover, the user need not think about the correctconnection of the device according to the invention to the controldevice, since the same control signal input of the device according tothe invention is used for the analog and for the digital control of theoperating means by the control device. Furthermore, the user can alsooptionally decide on the use of an analog or digital control device inthe lighting system subsequently, that is to say after the deviceaccording to the invention and the operating means have been installedin the lighting system. The evaluating means advantageously include aprogram-controlled microcontroller or a logic circuit. The deviceaccording to the invention is advantageously a component of an operatingdevice for electric illuminating means that has operating means for atleast one illuminating means. However, it is also possible to arrangethe device according to the invention outside an operating device forelectric illuminating means, and to provide signal transmitting means,for example cables, between the device according to the invention andthe operating means, arranged inside the operating device, for the atleast one electric illuminating means.

[0006] The method according to the invention for controlling operatingmeans for at least one electric illuminating means with the aid ofcontrol signals, generated by an external control device, and of adevice that has a control signal input for receiving the control signalsand also evaluating means for evaluating the control signals and forcontrolling the operating means comprises the following method steps:

[0007] applying a control signal to the control signal input andtransmitting the control signal to the evaluating means,

[0008] automatically testing the control signal with the aid of theevaluating means as to whether the control signal forms a valid digitalcontrol signal or a valid analog control signal or an invalid signal,and

[0009] evaluating the control signal and appropriately controlling theoperating means with the aid of the evaluating means if a valid digitalor analog control signal is present.

[0010] The method according to the invention permits optional control ofthe operating means of the illuminating means of an lighting system bymeans of analog or digital control signals that are generated by acentral control device of the lighting system in order to control thelighting functions. Moreover, independently of whether they are analogor digital, the control signals can be fed to the same control signalinput of each device according to the invention or each operating devicethat contains the device according to the invention. The devices oroperating devices therefore do not require separate control signalinputs for analog and digital signals. In the case of an analog drive ofthe devices or operating devices, use is advantageously made as analogcontrol signal of a periodic AC voltage whose peak value exceeds aprescribable threshold value representing the minimum permissible highlevel for digital control signals, and which assumes at least once perperiod a value below a prescribable second threshold value thatrepresents the maximum permissible low level for digital controlsignals. It is even possible in the case of such analog control signalsto use a single pushbutton for controlling the devices according to theinvention or operating devices of the lighting system. The methodaccording to the invention further permits additional control of thedevices or operating devices at the same control signal input by meansof a constant light regulation device.

IV. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The invention is explained below in more detail with the aid of apreferred exemplary embodiment. In the drawing:

[0012]FIG. 1 shows a schematic of a lighting system having operatingdevices according to the invention and a central control device workingwith the aid of digital control signals,

[0013]FIG. 2 shows a schematic of a lighting system having operatingdevices according to the invention and a central control device, workingwith the aid of analog control signals, comprising a single pushbuttonand a constant light regulation device,

[0014]FIG. 3 shows a flowchart that illustrates the method according tothe invention, in particular the change between the two operating modes,

[0015]FIG. 4 shows a flowchart for illustrating the analog control ofthe operating devices by means of a single pushbutton, and

[0016]FIG. 5 shows a schematic of a lighting system having operatingdevices according to the invention and a central control device, workingwith the aid of analog control signals, comprising a single pushbuttonand a motion detector.

V. BEST MODE FOR CARRYING OUT THE INVENTION

[0017] Illustrated schematically in FIGS. 1 and 2 in each case is alighting system having a multiplicity of operating devices B, B′according to the invention for electric lamps 4, 4′. The operatingdevice B according to the invention has electric terminals 1, 2 forsupplying power to the operating device, operating means 3 for at leastone electric lamp 4, electric terminals 10, 11 for the at least one lamp4, a control signal input with two terminals 8 a, 8 b that serves forcontrolling the operating means 3, and evaluating means 9 that detectand evaluate the control signals at the control signal input 8. Theoperating means 3 of the operating device essentially comprise anexternally controlled half-bridge inverter whose load circuit isdesigned as a series resonant circuit and provided with the terminals10, 11 for at least one electric lamp 4. The evaluating means 9 areconnected upstream of the externally controlled half-bridge inverter.They essentially comprise a programmable microcontroller that evaluatesunder program control the control signals present at the control signalinput 8 a, 8 b and converts them into corresponding signals for externalcontrol of the half-bridge inverter. The external control of thehalf-bridge inverter is carried out, for example, with the aid of anintegrated circuit designed specifically therefor and which generates,for example, pulse-width-modulated signals for controlling the switchingtransistors of the half-bridge inverter. The programmablemicrocontroller of the evaluating means 9 in this case takes overdriving the integrated circuit of the half-bridge inverter. Theevaluating means 9 are coupled to the terminals 8 a, 8 b of the controlsignal input, for example via an optocoupler and an overvoltageprotection circuit.

[0018] The evaluating means 9 and the control signal input with itsterminals 8 a, 8 b form a device C that need not necessarily be acomponent of the operating device B but can also be designed as aseparate assembly and can also, in particular, be arranged outside thehousing of the operating device B. In this case, each device C iscoupled to the operating device B assigned to it with the aid ofsuitable signal transmitting means, for example by interconnectingcables.

[0019] In accordance with the method according to the invention, theoperating devices B, B′ or the devices C, C′ can optionally be driven attheir control signal input 8 a, 8 b, 8 a′, 8 b′ with the aid of digitalor analog control signals. The digital drive of the operating devices B,B′ or the devices C, C′ is illustrated schematically in FIG. 1. For thedigital drive, the terminals 8 a, 8 b, 8 a′, 8 b′ of the control signalinputs of the operating devices B, B′ or the devices C, C′ are connectedto a central, digital external control device 7 that is provided withcontrol elements for controlling the lighting functions. The electricterminals 1, 2, 1′, 2′ of the operating devices 3, 3′ are connected tothe supply voltage lines N, L for the purpose of power supply. Thecontrol device 7 generates digital control signals that have aprescribed format. Each digital control signal comprises, for example,16 bits. It begins with a start bit and ends with a stop bit. The startbit is followed by the digitally coded operating address of theoperating device B, B′ to be driven, or of the group of operatingdevices that is to be driven, and one or more digitally coded controlcommands which change the operating state of the operating device or theoperating devices and the lamps connected thereto. In particular, thelamps 4, 4′ are switched on and off and dimmed by means of the controlcommands. The evaluating means 9, 9′ of each operating device B, B′ testthe control signal present at the terminals 8 a, 8 b, 8 a′, 8 b′ of thecontrol signal inputs as to whether a valid digital control signal ispresent, that is to say whether the control signal has the prescribedformat for digital control signals. In order to detect and to evaluatedigital input signals, a first threshold value, which defines a minimumvoltage value that is still rated as logic level “high” or “1”, and asecond threshold value, which defines a maximum voltage value that isstill rated as logic level “low” or “0” are stored in the evaluatingmeans 9, 9′. If a valid digital control signal is present at the controlsignal inputs 8 a, 8 b, 8 a′, 8 b′, the corresponding operating devicesB, B′ remain in the first operating mode of “digital drive”, or changeto this operating mode. The evaluating means 9, 9′ of the operatingdevices B, B′ use a microcontroller working under program control togenerate signals, corresponding to the digital control commands, forcontrolling the operating means 3, 3′. With each reception of a controlsignal at the control signal inputs 8 a, 8 b, 8 a′, 8 b′, a renewed testis made as to whether the control signal corresponds to the prescribedformat for digital control signals. If the result of checking thecontrol signal is that the latter does not correspond to the prescribedformat for digital control signals, a test is made as to whether thecontrol signal present at the control signal inputs 8 a, 8 b, 8 a′, 8 b′corresponds to the prescribed format for analog control signals. If thecontrol signal corresponds to the prescribed format for analog controlsignals, the operating devices B, B′ change into the second operatingmode of “analog drive”. The change between the two operating modes of“digital drive” and “analog drive” is therefore performed automatically,that is to say under program control, by the evaluating means 9, 9′ ofthe respective operating device B, B′. If neither a valid digitalcontrol signal nor a valid analog control signal is present, the signalpresent at the control signal input is ignored, that is to say, inparticular, the operating devices B, B′ retain their current mode ofoperation. The flowchart illustrated in FIG. 3 explains the changebetween the two above named operating modes.

[0020] The distinction between digital and analog control signals ismade by the evaluating means 9, 9′. For this purpose, the signal edges,detected within a prescribed time interval, of the control signal arecounted, and the number that is determined of detected signal edges iscompared with prescribed desired values for the digital and analogdrive, respectively. Since digital and analog control signals have verydifferent frequencies, this ensures a reliable distinction between thetwo types of signal. Moreover, it is also possible to distinguish inthis way between valid and invalid control signals. In the operatingmode of “analog drive”, the evaluating means 9, 9′ of each operatingdevice B, B′ use their microcontroller operating under program controlto generate signals, corresponding to the analog control signal, forcontrolling the operating means 3, 3′ of the respective operating deviceB, B′. The analog drive of the operating devices B, B′ of a lightingsystem with the aid of a single pushbutton 13 and a constant lightregulation device is illustrated schematically in FIG. 2. The analogcontrol, illustrated in the flowchart of FIG. 4, of the operatingdevices B, B′ is explained in more detail below.

[0021] As already described above, the operating devices B, B′ areoperated using system voltage. For this purpose, the electric terminals1, 2, 1′, 2′ of the operating devices B, B′ are connected to the supplyvoltage lines N, L. The analog control signals for the device C, C′ orfor the operating devices B, B′ are generated from the AC supplyvoltage. In order to generate the analog control signals, the supplyvoltage line N is additionally connected to the terminal 8 b, 8 b′ ofthe control signal input of each operating device B, B′ or each deviceC, C′, while the other supply voltage line L is additionally connectedvia the pushbutton 13 to the other terminal 8 a, 8 a′ of the controlsignal input of each operating device B, B′ or each device C, C′. Theanalog control signals are obtained from the AC supply voltage, ifappropriate after voltage division upon actuating the pushbutton 13. Theanalog control signals are therefore periodic AC voltages that areapplied briefly to the control signal input by actuating the pushbutton13. The actuation of the pushbutton 13 is detected by the evaluatingmeans 9, 9′. In order for the evaluating means 9, 9′ to be able todetect and evaluate the analog control signals, their peak value isselected such that it exceeds a first threshold value, that in the caseof digital control signals, defines the minimum voltage value stillvalid as logic level “high” or “1”. Moreover, the analog control signalsare designed such that at least once per period they undershoot a secondthreshold value that, in the case of digital signals, defines themaximum voltage value still valid as logic level “low” or “0”. It isthus ensured that the evaluating means 9, 9′ detect changes in theanalog control signal, in particular the actuation of the pushbutton 13.The precise sequence of the control of the operating devices B, B′ orthe devices C, C′ by means of analog control signals is illustrated inthe flowchart of FIG. 4.

[0022] If the pushbutton 13 is briefly closed with the lamps 4, 4′switched off, the lamps 4, 4′ are switched on at the reclosing value,stored in the operating device B, B′, for their dimming level orbrightness level. If the pushbutton 13 is closed for a lengthy time withthe lamps 4, 4′ switched off, the lamps 4, 4′ are switched on at minimumbrightness and their brightness is increased as long as the pushbutton13 is closed, or until the maximum brightness is reached. Upon renewedactuation of the pushbutton 13, the direction of brightness control isreversed, that is to say a changeover occurs from “raising” to“lowering” the brightness. The lamps 4, 4′ remain in the switched-offstate in the event of an invalid actuation of the pushbutton 13.

[0023] If the pushbutton 13 is briefly closed with the lamps 4, 4′switched on, the current brightness value of the lamps 4, 4′ is storedas reclosing value, and the lamps 4, 4′ are subsequently switched off.If the pushbutton 13 is closed for a lengthy time with the lamps 4, 4′switched on, and if the direction of brightness regulation is set on“lowering”, the brightness of the lamps 4, 4′ is reduced for as long asthe pushbutton 13 remains closed, or until the lamps 4, 4′ have reachedtheir minimum brightness level. Upon renewed actuation of the pushbutton13, the direction of the brightness regulation is set to “raising”. Ifthe pushbutton 13 is closed with the lamps 4, 4′ switched on, and if thedirection of brightness regulation is set on “raising”, the brightnessof the lamps 4, 4′ is raised for as long as the pushbutton 13 remainsclosed or until the lamps 4, 4′ have reached their maximum brightnesslevel. Upon renewed activation of the pushbutton 13, the direction ofthe brightness regulation is set to “lowering”. In the case of aninvalid actuation of the pushbutton 13, the lamps 4, 4′ remain in theswitched-on state.

[0024] The lighting system illustrated schematically in FIG. 2additionally has a constant light regulation device which is fitted witha light sensor 12 and controls the brightness of the lamps 4, 4′ as afunction of the ambient light so as always to ensure a constant level oflighting or brightness. The output circuit of the sensor 12 of theconstant light regulation device is designed such that no sensor signalis present at the control signal inputs 8 a, 8 b, 8 a′, 8 b′ of theoperating devices B, B′ or the devices C, C′ as long as the pushbutton13 is closed. After each change in the brightness value owing to anactuation of the pushbutton 13, the frequency of the sensor AC voltageis measured and used as new desired value by the operating devices B, B′for the purpose of brightness regulation of the lamps 4, 4′. If theactual value of the frequency of the sensor AC voltage differs from thecurrent desired value, the operating devices B, B′ correct theirbrightness level until the actual value of the frequency of the sensorAC voltage again corresponds to the desired value. The frequency of thesensor signal, generated by the constant light regulation device, at thecontrol inputs 8 a, 8 b, 8 a′, 8 b′ is, for example, between 200 Hz and400 Hz. The frequency of the system AC voltage, and thus also thefrequency of the control signals that can be influenced by thepushbutton 13, is outside the frequency range of the sensor AC voltage.

[0025] The invention is not limited to the exemplary embodimentsexplained in detail above. A further exemplary embodiment of theinvention with analog drive by a pushbutton 13 is illustrated in FIG. 5.This exemplary embodiment is largely identical to the exemplaryembodiment of the invention illustrated in FIG. 2. The sole differenceconsists in the assembly 12. In FIG. 5, the reference 12 denotes thecombination of a light sensor and a presence detector that detects thepresence of a person in the region of the illuminating means andswitches on or off appropriately. The presence detector or light sensorcan be activated or deactivated via the switch S. The constant lightregulation device also works here as has already been described abovewith the aid of FIG. 4. Consequently only the functioning of thepresence detector is explained in more detail below.

[0026] The sensor of the presence detector, which is designed as amotion sensor, for example, supplies an AC voltage signal of fixedfrequency directly after detection of the presence of a person, thefrequency of this AC voltage signal being outside the frequency of thedigital drive or of the analog pushbutton drive and outside thefrequency range of the light sensor. A timer for a settable delayinterval is activated in the motion sensor of the presence detector withthe output of the above named AC voltage signal. The timer is reset toits initial value with each movement. As long as the delay interval hasnot expired, the sensor periodically continues to supply an AC voltagesignal. The brightness value required for the constant light regulationcan be received between the AC voltage signals of the presence detector.If an operating device receives no AC voltage signal from the presencedetector over a specific time interval, the operating device sets thebrightness to the lowest value and finally switches off.

[0027] Another possibility for controlling the presence detectorconsists in not communicating any AC voltage signals from the presencedetector within the above named delay interval. Rather, instead of thisat the end of the delay interval the presence detector supplies an ACvoltage signal of changed frequency that causes the operating device toset the lowest brightness value and switch off. In all cases, thepushbutton signal has priority over the control signals of the lightsensor or presence detector.

[0028] It may be stressed here once more that all control devices,whether pushbutton 13 or light sensor 12 or presence detector or digitalcontrol device 7, use the same control signal input 8 a, 8 b of theoperating device. The operating device B automatically detects whichtype of drive is present and evaluates the control signalscorrespondingly. Moreover, the light sensor 12 or the presence detector12 reports automatically to the operating device by means of its ACvoltage signal. There is no need to restart the system in order todetect the newly connected control devices. The light sensor 12 orpresence detector 12 can even be switched off temporarily by means ofthe switch S. There is no need even then to restart the system in orderto detect the connected sensors.

What is claimed is:
 1. A device for controlling operating means for atleast one electric illuminating means, having a control signal input forreceiving control signals from an external control device, evaluatingmeans for evaluating the control signals and for controlling theoperating means, wherein the evaluating means are suitable forautomatically detecting both analog and digital control signals at thecontrol signal input, and for evaluating them for the purpose ofcontrolling the operating means.
 2. The device as claimed in claim 1,wherein the evaluating means include a program-controlledmicrocontroller.
 3. The device as claimed in claim 1, wherein the devicecan be connected to an operating device that has operating means for atleast one electric illuminating means.
 4. The device as claimed in claim1, wherein the external control device is a pushbutton or a light sensoror a presence detector or a combination of presence detector and lightsensor or a digital control device.
 5. An operating device havingoperating means for at least one electric illuminating means,characterized in that the operating device has a device as claimed inclaim
 1. 6. Use of the control signal input of a device that has thefeatures of claim 1 in order optionally to receive digital or analogcontrol signals.
 7. A method for controlling operating means for atleast one electric illuminating means by means of control signals,generated by an external control device, with the aid of a device thathas a control signal input for receiving the control signals andevaluating means for evaluating the control signals and for controllingthe operating means, wherein the method has the following method steps:applying a control signal to the control signal input and transmittingthe control signal to the evaluating means, automatically testing thecontrol signal with the aid of the evaluating means as to whether thecontrol signal forms a valid digital control signal or a valid analogcontrol signal or an invalid signal, and evaluating the control signaland appropriately controlling the operating means with the aid of theevaluating means if a valid digital or analog control signal is present.8. The method as claimed in claim 7, wherein a pushbutton is used todrive the at least one device by means of analog control signals at thecontrol signal input.
 9. The method as claimed in claim 8, wherein aperiodic AC voltage is used as analog control signal, in which case thepeak value of the AC voltage exceeds a prescribable first thresholdvalue that represents the minimum permissible logic level “high” or “1”for digital control signals, and the AC voltage assumes at least onceper period a value below a prescribable second threshold value thatrepresents the maximum permissible logic level “low” or “0” for digitalcontrol signals.
 10. The method as claimed in claim 7, characterized inthat control signals from a light sensor are applied to the controlsignal input.
 11. The method as claimed in claim 7, characterized inthat control signals from a presence detector are applied to the controlsignal input.
 12. The method as claimed in claim 7, characterized inthat control signals from a light sensor and a presence detector areapplied to the control signal input.